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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/hwmon/lm75.h
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/hwmon/lm75.h')
-rw-r--r--drivers/hwmon/lm75.h41
1 files changed, 41 insertions, 0 deletions
diff --git a/drivers/hwmon/lm75.h b/drivers/hwmon/lm75.h
new file mode 100644
index 000000000..b803ada5e
--- /dev/null
+++ b/drivers/hwmon/lm75.h
@@ -0,0 +1,41 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * lm75.h - Part of lm_sensors, Linux kernel modules for hardware monitoring
+ * Copyright (c) 2003 Mark M. Hoffman <mhoffman@lightlink.com>
+ */
+
+/*
+ * This file contains common code for encoding/decoding LM75 type
+ * temperature readings, which are emulated by many of the chips
+ * we support. As the user is unlikely to load more than one driver
+ * which contains this code, we don't worry about the wasted space.
+ */
+
+#include <linux/minmax.h>
+#include <linux/types.h>
+
+/* straight from the datasheet */
+#define LM75_TEMP_MIN (-55000)
+#define LM75_TEMP_MAX 125000
+#define LM75_SHUTDOWN 0x01
+
+/*
+ * TEMP: 0.001C/bit (-55C to +125C)
+ * REG: (0.5C/bit, two's complement) << 7
+ */
+static inline u16 LM75_TEMP_TO_REG(long temp)
+{
+ int ntemp = clamp_val(temp, LM75_TEMP_MIN, LM75_TEMP_MAX);
+
+ ntemp += (ntemp < 0 ? -250 : 250);
+ return (u16)((ntemp / 500) << 7);
+}
+
+static inline int LM75_TEMP_FROM_REG(u16 reg)
+{
+ /*
+ * use integer division instead of equivalent right shift to
+ * guarantee arithmetic shift and preserve the sign
+ */
+ return ((s16)reg / 128) * 500;
+}